Regulating mechanism for arc-lamps.



a. M. ume.

REGULATING MECHANISM FOR ARC LAMPS.

APPLICATION FILED FEB.3. 1M5.

1,255,445. Patented Feb. 5,1918.

WITNESSES INVENTOR Q Geg yeM. LITT/e.

ATTORNEY UNITED STATES PATENT OFFICE.

GEORGE M. LITTLE, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

REGULATING MECHANISM FOR ARC-LAMPS.

Application filed February 3, 1915.

To all whom it may concern:

Be. it known that I, GEORGE M. LITTLE, a citizen of the United States, and a resident of Pittsburgh, Pennsylvania, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Regulating Mechanism for Arc Lamps, of which the following is a specification.

My invention relates to are lamps, and it has special reference to improvements in the clutching and regulating mechanisms for such lamps.

More particularly, my invention relates to a focusing arc lamp in which the regulating functions are performed in connection with one electrode, the other electrode being stationary and preferably non-con sumable in the arc.

Arc lamps are ordinarily provided with clutches that engage and support the movable electrodes and are adapted, in connection with the regulating mechanism, to adjust the relative positions of, or distances between, the arcing ends of the electrodes. Consumable electrodes, as supplied commercially, have slightly varying diameters. Moreover, clutches engaging such electrodes are subjected, in service, to wear.

It is desirable to have a pick-up of constant length for a given movement of the clutch-supporting rod in an arc lamp, irrespective of the dimensions of the electrodes supplied thereto or to the worn condition of the clutches, and, to accomplish this, I have devised the present clutching mechanism. Moreover, my lamp-regulating mechanism i very simple in construction and comprises a few members only which are so correlated as to minimize greatly the frictional resistance that is usually inherent in lampregulating mechanisms. In addition thereto, the pick-up length remains substantially constant under all conditions, while the electromagnetic operating device which actuates the regulating mechanism may be economically constructed because of the satisfactory counter-balancing of the active members and the lack of excessive frictional resistance.

My invention is illustrated in the accompanying drawing in which the single figure is a side elevation, partially in section, of the principal operating parts of a lamp constructed in accordance with my invention.

I have shown my invention as applied Specification of Letters Patent.

Patented Feb. 5, 1918.

Serial No. 5,891.

to an electric headlight, such as is used on electric locomotives or electric cars. When thus employed, it is unnecessary to provide an automatic feeding mechanism for intermittently feeding the consumable electrode in the arc, inasmuch as the lamp will operate satisfactorily for the required time without feeding the consumable electrode into the arc. Of course, it will be understood that my invention is not necessarily limited to use in electric headlights but may be embodied, with equal effectiveness, in other types of arc lamps.

Referring to the drawing, a movable and consumable lower electrode 1 cooperates with an upper stationary electrode 2 to maintain an are between the opposing ends thereof. Inasmuch as the upper electrode 2 is stationary by reason of its engagement with a support 3 which is secured to a frame 4 of the lamp, the arc-regulating functions of the lamp must be performed in connection with the lower electrode 1. To permit egress of the arc vapors generated in an inclosed are chamber 5, a draft tube 6 is provided which loosely embraces the upper electrode 2 and communicates with the outer air by means of a perforated cap 7 of well known construction. The draft tube 6 registers with a downwardly projecting tubular portion 8 of the cap 7, as shown in the drawing.

To support the upper electrode 2, which is preferably made of copper or some other material which is non-consumable in the arc, this electrode is provided with a forwardly extending portion 9 which projects through a slot formed in the draft tube 6 and engages the spaced walls of the holder 3. A cotter pin 10, projecting through} openings in the holder 3 and the extending portion 9 of the electrode 2, securely holds the electrode 2 in a fixed position. A refiector 11, secured to the frame of the lamp, is so disposed as to forwardly project the light emitted from the arc.

Inasmuch as the upper electrode 2 is stationary, the regulating functions of the lamp are performed in connection with the lower electrode 1, and, to this end, a clutching mechanism, embodying a form of my invention, is provided. The clutching mechanism comprises a rocker arm 12 which is pivotally mounted upon a support 13, a magnetizable member 14, which is rigidly secured to one end of the arm 12, and a clamp 15 which engages the lower electrode 1. A free end 16 of the rocker arm 12 projects through a slot 17 formed in an upright movable member 18. Whlle the member 18 may be supported 1n any one of several ways, I have shown it sup orted by means of arms 19 and 20 whic ro ect from the lamp frame 4. The mem er 18 is precluded from moving laterally by reason of bearings 21 secured to the arms 19 and 20 and with which the member 18 slidingly engages. By reason of this construction, the member 18 is free to move upwardly or downwardly. The downward movement of the member 18 is restricted by means of a clutch ring 22 which is pivotally secured, at one end, to a member 23, and, at the other end, to a spring 24. One end of the member 23 is secured to a fixed support 25 which may be attached to the lamp frame in any suitable manner. The spring 24, which engages the outer end of an arm 26, is preferably of a very llght construction in order to impose but little restraint upon the movement to the clutch ring 22.

In order to understand more fully the operation of my device, assume that an electromagnet 27 is denergized, thereby permitting the armature 14 to descend. This movement causes the electrode 1 to move upwardly toward the electrode 2 and the free end of the arm 16 to engage the upper wall of the slot 17 in the member 18. The member 18 will move concurrently with the rocker arm 12 until the arcing ends of the electrodes 1 and 2 are in contact. As the member 18 moves upwardly, the clutch ring 22 offers no resistance thereto. When the electromagnet 27 is subsequently energized, the armature 14 is attracted upwardly, thus causing the electrodes 1 and 2 to draw the arc. As the end 16 of the arm 12 moves downwardly, the clutch ring 22 will engage the member 18 after engagement is efi'ected between the arm end 16 and the movable member 18.

The slot 17, being of a predetermined length,-

limits the movement of the rocker arm 12, thereby insuring a pick-up of constant length at all times.

N o mechanism is disclosed for automatically and intermittently feeding the consumable electrode 1, inasmuch as the service to which my arc lamp is particularly adapted does not require long continuous burning of the arc. However, it will be understood by any one skilled in the art that a feeding mechanism may be provided which will intermittently feed the lower electrode 1 into the arc as it is consumed.

The electromagnet 27 is shown as of a particular type of construction, but other types of electromagnets may be used which will effectively act upon the magnetizable member or armature 14. The electromagnet 27 comprises an energizing winding 28 which embraces a magnetizable core member 29. A yoke 30 of a well known type of construction exteriorly engages the coil 28, thereby insuring a very strong electromagnetic field to actuate the armature 14.

While I have shown and described one embodiment of my invention, it will be understood by those skilled in the art that many modifications may be made wlthout departing from the spirit and scope of the appended claims.

I claim as my invention:

1. An arc lamp comprising an electrode holder, a rocker arm supporting the said electrode and pivotally supported intermediate its ends, .means for effecting movement of said arm, a slidable member provided with a slot through which one end of said rocker arm projects, and means for permitting said member to move longitudinally in one direction but which precludes movement thereof in the opposite direction.

2. An arc lamp comprising an upright electrode, a pivotally mounted transverse member which supports said electrode, means for efi'ectin movement of the transverse member, a slldable upright member provided with a slot through which one end of said transverse member extends and which is of suflicient extent to permit relative movement between the said transverse member and the said upright member, and means for permitting said upright member to move in one direction but precluding movement thereof in the other direction.

3. An are lamp comprising an upright electrode, a pivotally mounted transverse member which supports said electrode, means for elfecting movement of the transverse member, a slidable upright member provided with a slot through which one end of said transverse member extends and which is of suflicient extent to permit relative movement between the said transverse member and the said upright member, and means for permitting said upright member to move freely in one direction only.

4. An arc lamp comprising an upright electrode, a pivotally mounted transverse member which supports said electrode, means for effecting movement of the transverse member, a slidable upright member prothrough which one end of said rocker arm projects, and a pivotally secured clutch ring which embraces said upright member and permits it to move longitudinally in one direction but precludes movement thereof in the opposite direction.

6. An arc lamp comprising an electrode holder, a rocker arm supporting the said electrode holder and pivoted intermediate its ends, means for actuating said arm, a unidirectional slidable member, and a lost-motion connection between one end of the said rocker arm and the said slidable member.

7. An arc lamp comprising an electrode holder, a rocker ar'm supporting the said 5 electrode holder and pivoted intermediate its ends, a slidable member provided with a lost-motion connection with respect to the said rocker arm, and means for permitting longitudinal unidirectional movement of the said slidable member.

In testimony whereof, I have hereunto subscribed my name this 30th day of Jan.

GEORGE M. LITTLE. Witnesses:

B. B. Hmns, M. C. MERZ. 

